1. Field
The present disclosure relates to the field of non-volatile digital memories, and in particular to a non-volatile digital memory based on thin film resistors.
2. Description of the Related Art
It has been proposed to use fuses or anti-fuses to provide a digital memory used in circuit trimming. Circuit trimming involves adjusting one or more operating parameters of an electronic circuit after fabrication. The state of the fuses or anti-fuses for example controls a MOS transistor network, which sets the value of one or more circuit components, such as resistors or capacitors, in the circuit. Fuses or anti-fuses provide non-volatile data storage of the trimming information, the state of the fuses being permanently maintained irrespective of the presence or absence of a supply voltage to the circuit.
A drawback of such a non-volatile memory is that the fuses or anti-fuses generally require relatively high voltages and/or currents for burning them. Such voltages/currents are not compatible with the normal relatively low supply voltages of the circuit, which is problematic in the case that trimming is performed after packaging without using a dedicated test pin, and leads to difficulties in integrating such a non-volatile memory in an integrated circuit.